1 files changed, 53 insertions, 0 deletions
diff --git a/arch/mips/math-emu/dp_flong.c b/arch/mips/math-emu/dp_flong.c
new file mode 100644
index 000000000..681ee00c9
--- /dev/null
+++ b/arch/mips/math-emu/dp_flong.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* IEEE754 floating point arithmetic
+ * double precision: common utilities
+ */
+/*
+ * MIPS floating point support
+ * Copyright (C) 1994-2000 Algorithmics Ltd.
+ */
+
+#include "ieee754dp.h"
+
+union ieee754dp ieee754dp_flong(s64 x)
+{
+	u64 xm;
+	int xe;
+	int xs;
+
+	ieee754_clearcx();
+
+	if (x == 0)
+		return ieee754dp_zero(0);
+	if (x == 1 || x == -1)
+		return ieee754dp_one(x < 0);
+	if (x == 10 || x == -10)
+		return ieee754dp_ten(x < 0);
+
+	xs = (x < 0);
+	if (xs) {
+		if (x == (1ULL << 63))
+			xm = (1ULL << 63);	/* max neg can't be safely negated */
+		else
+			xm = -x;
+	} else {
+		xm = x;
+	}
+
+	/* normalize */
+	xe = DP_FBITS + 3;
+	if (xm >> (DP_FBITS + 1 + 3)) {
+		/* shunt out overflow bits */
+		while (xm >> (DP_FBITS + 1 + 3)) {
+			XDPSRSX1();
+		}
+	} else {
+		/* normalize in grs extended double precision */
+		while ((xm >> (DP_FBITS + 3)) == 0) {
+			xm <<= 1;
+			xe--;
+		}
+	}
+
+	return ieee754dp_format(xs, xe, xm);
+}